In the introduction of my thesis I want to motivate the use of alternative neutron converters to helium-3 by mentioning the exploding cost of latter.
I am not directly involved with helium-3, since I work with the alternatives. Online research yielded for instance a congressional research paper by Shea and Morgan from 2010, and the wikipedia page for helium-3 links to an IEEE site also from 2010, mentioning the price explosion in that year.
Is one of those source apt for citation? Is there a best way to cite prices in academia?